Machine tool



May 17, 1938. M, s. CURTls' l l 2,118,022

MACHINE TOOL Original Filed F'eb. 9, 1931 7 Sheets-Sheet 1 625/0 l/d/ue (ever /9 ATTORNEY May 17, 193s.. M s C-URTIS- 2,118,022

' MACHINE TOOL original Filed Feb'. 9, 1931 K 7 sheets-sheet 2 [NTOR Y Y Ml l` v M. s. CURTIS MACHINE 11001J Original Filed Feb. 9, 1931 INVENTOR Q&M\ A TTORNE Y May 17, 193s.

Mayu,A 1938. 4M. s;` CURTIS MACHINE TOOL '7 Sheets-Sheet 4 Original Filed Feb. 9, 1931 V NTOR y @Q5-W@ ATTORNEY May 17,'1938. M. s. CURTIS 2,118,022v

' MACHINE TOOL Y original Filed Fe. 9, i931 `'7 sheets-sheet 5 Elly/Low.

ATTORNEY May 17, 1938.

M. s. vCURTIS 2,118,022 i MACHINE Toi. l l original Filed Feb. 9, 1951 '7 sheets-sheet e /76 /42 A76. /0

Wam

ATTORNEY M, s. CUR-ns MACHINE TOOL May 17, 1938.

original Filed Feb. v9,l 1931 7 SheetSfSheet 7 NRT m\\ bex mism. uwoxn j? N'roR *l /ZBY LM' ATTORNEY wPatented May 17,119.38

momma 'rooL Mymi s. cuna, rawtueket, a. 1.,ueignei-:e

William Wallace Potter, Pawtucket, R. I.

February a, 1931, serial No. 514,661v

Renewed July 8, .1937 j Application My'invention consists of improvements in ma-4 chine tools for turning,` boring and the like.

In my speciiication as an exempliiication vof my invention, I describe a machine for turning work f on centers, .but my' invention Vis applicable to other machines, forexample those inA which work is he1d in a. chuck. I do not limit myself to thel center turning type of. machine. Among thefeatures of my invention and the advantages which I obtain by my improvements are:

IJMinimum of floor space and ease oi opera# s tion,-by virtue of the vertical construction em-- i 2. Rigidity andfstrength o; construction, and cheapness of manufacture and ease of alignment by using bars tovextend between and connect the stationary members to constitute frame meme bers and 'at the same timemake them serve guides vor ways for the slidable machine members; v

3. .Ease .of adaptation to a mechanical feed machine or to a' hydraulic feed machine;

4. Supporting and operating a tailstock. whereby the J.,work'is more rigidly and securely held than usual; and the tailstock center is conveniently moved and clamped; I

5. Construction of slides and slide base (or carriage) whereby one set of slides may be'convens iently substituted for another; v 6. Construction whereby the capacity of the '30 machine may be altered by simply changing the length of the supporting bars;

'1. 'operation ef' tailstoek center, by immuneA A construction oi' Vhydraulic feed control,

3" whereby one or more machines may be operated from an accumulator, with minimum of parts and valves;

9. A metering valve foraI hydraulic system,

40 and minimizes or obviates the effects due to wire drawing, dirt in the iluid, etc.; and 10. Novel resistance valves or regulators lfor ,operating the control valves of vthe hydraulic' Figure 3 is a partial side velevation of Fig. l,

,55 looking in the direction of the arrow in Mg. l;

which gives an even flow at all degrees of opening (ci, aas-zi y lligure 4 is 'across-section vof Fig. 3, substantially on the line 4-4;

Figure-iis a iront elevation, enlarged, ofthe tailstocir center and support; l ll'igure is a plan view oi Figure 5;

Figure 'I is a front elevation ofthe right hand. hydraulically operated tool slide of Fig. 1;

'.Figure 8 isa plan view of Fig. '1; Figure 9 is a sectional view substantially on th Figure 10 is a top view of Fig. l, with the feed .plate cover removed: e

Figure l1' is a front elevation ci the feed plate .and hydraulic cylinders of Fig. 1, with the cover removed; l' i' Figure 12 isa sectional view of the tailstock actuating means and taken substantially on line I2-I2 ofFig. 11; and' Figure 13 is a diagrammatic view of the hydraulic cylinders, ',valves, etc., of one slide unit.

'Ihe machine, as illustrated, has two units,-

that is, two carriages 22, one on the right hand and the'other onthe left hand side of the ma-v chine, each having a tool's'lide |06 mounted thereon and each right and left hand carriage and its @slide having its separate and necessary operating mechanisms;.but, as the units are alike in construction and functions, although. independent oi each other, I shall describe the right hand unit only, and like numbers refer`t`o like parts ofthe Base lIl 'has secured to and extendingmpwar therefrom. four parallel posts or bars II and I2, in two pairs. Bars II are each ilrmly held in bearings I3 and," in bottom and top of base Il and serve as the main support and guide bars.

Cab

Bars f2 are each rmly heldin bearings I5 inthe f top only of base III, and serve'as auxiliary "supports and guides. These bars II and I2 extend the tailstock support Il and the other end of .which is .fixed in vfeed plate I6, and, when located 'in the desired Position, may be securely l clamped by means of caps 2li, and binder screws '2I. The carriages 22 (Figs, 1, 2, 'l and 8) also 0 upward to the feed plate I6, where they are A may be easily and convenientlyv attached and rejoperating mechanism and the tailstock support |6 supports the tailstock 56.

misma heid from twisting' with relrztion totahspk 5s by'stud 12, which also ser 2 may be slidably mounted on each pair of .bars and l2, respectively. Each carriage 22 is made with a removable cap 24 (see Fig. 8) so that they atedby stud 66 and pinionv60'. Rod 10 is free to slide in body 56, between collar 15 threaded to rod 19 and 'stop button 16, with which the end ot roet 10 contacts;Y Spring 11, held between collar 16 on rod 16 and cap 19 on body 56,. tends .to hold body 66 and rod 10 in therelative position shown.l Instead of the center 60, the tailmoved. These are described fully hereatnter.

The base I contains the spindle operating mechanism; the feed plate I6 supports the/feed Base construction and spindle df'iey d Basev lu is formed with a rim or 11p z5, which x element. forms a container for chips, the bottom of which Y' Operation is asjollows: Assume the tailstockv s the same purposel fordthe second clamping plate 13 which is operstock mayV carry a tool or other work engaging is S0 sloped that the Chips tend to slide down body 56 to be inthe position shown which isat` f fastened to the base I0, by screws 3l, is bushing l race 31 of an anti-friction bearing, the inner nut 42, byr which the position of bushing 36 may inner bearing race 35 oi which is on the spindle .25

the top end of its stroke with nut v61 `loosened by rack 69 and pinion 66. A piece of work is placed on the spindle center 26a in such a position that downward movement of the tailstock body will cause center 66 to engage a center hole in the end ofthe work-piece when rod 16 is moved downwards, aslhe'relnafter described. As clamp- 32, in which is fixed by means 0f 841 33. Outer .ing plates 1| and 13 are now loose, body 56 is bearing race 34, of an anti-friction bearing, the suspendedvby'od `1|; tm-Qugh nut 15 and plate 19. Therefore.- when rod 16 is moved downwards by means hereinafter described, the combination of the weight of body 56 and the compression oi spring 11 causes body 56 to move downward carrying the center 60 against the work and bringing body 56 to rest.` Further movement of vthe rod 16 compresses spring 11 and causes rack .69 to rotate pinions 68 and 66 which thread nuts 61 on their respective studs 65 and 66 to tighten clamping plates 1| and13 to the tailstock support I6. Adjustment nuts 14V allow any degree of clamping tension' to be obtained. When it is desired toremove the. piece of work from the centers, rod 1U is moved in an upward direction, and the construction just described allows the Slidably but not rotatably located Jin bearing surface 30 is bushing 36, containing the outer race 36 of whichis Aon the spindle 26.

Keyed to'spindle 26 is gear spider 39kto which is fastened wormgear 40 and by nut 4'|,-1inner bearing races 34 and 36'and worm gear spider 39 are all clamped to spindle 26. The spindle A26 may be provided with any typeof work-pieceengaging element such as acenter 26a.A

Bushing 36 has screwed to its lower end a be regulated which, in turn, regulates the amount of initial thrust placed on the spindle anti-friction bearings.

Meshing with worm gear 40 is worm 46 keyed to shaft 44 supported inbearings in the base l0 bodyA 56, whereby the rack 19 rotates pinions 66 and in the reverse direction, thus releasing the clamps, until 4collar 15 is brought up against and which shaft has removably keyed to-one end f the Shoulder on cap 19 thereupon further plate 48, (see Figs. 3 and 4) chain 53 and sprocket 54, drives tlel lubricating change gear 45 meshing with change gear 46 removably keyed to shaft- 41, access to these changegears belng'had by means pf removable mt mustk body 55' The rod 19', which operates the tailstock, has piston 6| ilxed to its upper end and slidable in c nder 62 (see Fi 10, A11 v12 li meshing with pinion 56 on the shaft of motor .5| nrecewes mud eitgtr from :E: usidgolgg;

and through these spindle 26 is driven by motor or. from L pipe |42 (Fig. 10) through pipe 63 and 5|. Keyed to ,shaft 41 is sprocket 62,- which by valve sings nu and the e l ust from the cy1 At the other endo: shari; n is keyed g'ea '49,

rod 19 to'move longitudinally with respect tov movement'of rod 16 in' an upward directionwill 5.

inder is delivered throughpipe' 61 to a drain.

Pump -1 l i ma Piston u and through itl rod-1o and tail Taikmck construe@ g stock vbody .56, are controlledv in movement by Slidably mginted in the tailstock support i6. handv lever 99 which operates a-pilot valve 92aiS a 'tailStOek bOdY 56 Which i5 bored't 011e endv in a valve casing 62a on cylinder` 92 as follows: vAn

Y t0 hOld thelive tailtok Center/"0. which' my extension 9| on hand leveig is connected with 'The tailstock body 66 isheld to base I6 by straps 69 on operating rod 1|I. 'Ihe other end of stud be carried in a sleeve 51. rotatableJ inanti-friction valve rod 92 'so that movement of the hand lever bearings 56 and 59, but not free to move longireciprocates the valve rod 92 and the pilot valve tudinallyl The sleeve`51 holds the tailstock center 92a.. with the valve a in the upper position shown, fluid enters'fhev valve casing through pipev 60 or some other typeof work supporting means.

63 and portl 99 and'passes to portl 94 which is connected by port 95 with the upper end oic' the cylinder. 62 and acts on piston 6| to' torce it f fdown'. lThe uid on the underside of piston'll is forced out through port 96a to port v96, where 6| and 62v and adjustable gibs 69 and 'andis' bored` to receive studs and 66. .These studs with their operating mechanism (see Figs. 5 and Stud 65 is threaded on one end for engagement with a nut 61, which has fast toit a pinion 6 6. This pinion meshes with andis operated by rack Det Valve 96 Aagainst the Pl'gssure of adlustble spring' 99, escapes into exhaust port 61 through portl |6I.

65 .passes through a hole in clamping plate 1| -"When valve rod 92 is pulled 'down by means' of and is provided' with adjusting 'nuts 14 for the purpose of handadjustment. Clamping plate 1|,

which clamps tailstock 5s to carriage Il', is free passes to port 9B and thence to the underside 0f to slide longitudinally withtailstock 66, but is piston 6| by means` of port 96a, the tluid on top itpasses by the .valve to port-91, and lifting pop- "hand lever l99, uid enters through port 93.A

'arianna of piston 8| being displaced through ports 85,' 84, and passage 84a to exhaust pipe 81.

It will be noted that in the upward movement of piston 8|, the exhaust flows freely to pipe 81,

whereas in its downward movement it is necessary for the exhaust to lift poppet valve 88. The reason for thisv is three-fold: First, ifv the fluid were free to exhaust from the under side of the` piston when the pressure was shut off from the pipe 88 for any reason,`.the weight of the tail-l stock body-would cause the tailsiock and pston able to retract thevtailstock center than to ad vance it.. Due to the area of the` piston rod 10 there is in ore working area on piston 8| .to push it down than to .push it upf .I remedy this difliculty,by applying a back pressure to the bottom side' of piston 8| by means of spring controlled ppp'et valve 98, so that there is extra back pres-v sure on the bottom of the piston when the pis ton is being forced down. A Y,

I Hydraulic slide construction 'e The construction ofthe hydraulic carriage and `slide are best shown onlilgs. 7, 8 and 9, which by gland |l4, and the other end by cap ||5.,

show-the right hand carriage and slide of Fig. 1. vThe carriage or slides'base 22, as before explained, has a cap 24 boltedvto it by bolts |02 'so thatl when .bolted together the two form a This is bored out to hold bush' unitary base. ings |08 and |04 which Yslidably fit o bars- |I and-J2, respectively.

. .Carriage 22 is providedwith ways |05 (Figs.

2 and '1) in which is suda'bly mounted slide In xed to which is tool block |01 holding tool I I8,

or some such arrangement 'for cutting work. Se.

curely fastened in slide |08 by stem |08 and nut I I0 is rod III, one lend oi which forms piston I |2 which slides in cylinder ||8, which is a part of carriage 22. One end of the cylinder is closed Fluid reaches the 'outer4 side of the piston Il! through port |I8 and pipe ||1, and .reaches the inner side of the piston through ports III, `II8 and |20, which are drilledin'carriage 22, pipe1A |2I, port- |22, which are in' cap, III, and p'pe |23, so that by applying' pressure on one'slde-or the other of piston' |22, the piston may be moved in the cylinder: and cause the slide |00 to traverse either inward or; outward on guideways ||5 on carriage 22. l

Carriage' 22 is movable'vertically by push rod |24, the lower end of which is threaded and securely but adjustably held in carriage 22' by col,-

lars` |25 and |26. The operation o'f rod |24 and.

controljof the flow of iluid tothe cylinder ||8 is lhereinafter described. The slide |08 is stoppedl at thefed of its inward movement by adjustable stop screw |21, ,andn at the end of'its return stroke by adjustablestop screw |28 engaging with gland |'|4` (see Flg..9), and carriage 22 is stopped at the end of its downward stroke by adjustable `stop screw |28 (see Fig.` 1) onthe base'l0 and is limied in its upward movement by adjustable l screw.|`30 on'tailstock support I8. As carriage 22 vmoves up 'and down pipes ||1'and |28 which are carried by the cylinder cap ||5 on said car rlag'e, slide up and vdown in trombone |8I.l Adl y justably bolted to slide |05 is dog |82 which coactsJ with finger |88 'on lever |84 'to cause partial rotation of shaft or rod |85, which shaft controls the change from fast ahead to feed ahead in a wfa'y hereinafter described.

It isometimes' 'desirable to have the cutng tool |08 follow an angular or curved path;\.this is accomplished by moving slide |06 either in or out at the same time that carriage 22 is moving upwards or downwards. For. that.'- purpose, securely fastened to the carriage 22 .is housing |88 .'(see Figs. 1, 'l and 8) in which is slidably-mouhted cam bar |31 on which is formed cam |88. The upper end of cam bar |31 isfastenedby rod |88a to feed plate I6. so that it is held stationary and;

therefore, as carriage 22 moves either up or down, cam bar |31 and thus cam.v |88 is moved relatively to it.- Fastened to the rear or outer endl of slide IIlSV andfco-actizg with cam |88 is follower block |40. At the beginning of a cycle slide |05 will be 'pushed in by fluid pressure entering cylinder ||8 through pipe ||6 and acting against the outside of piston I|2 until cam follower I 4l touches cam 488, Longitudinal movement of 'carriage 22 will now cause relative movement oi' cam |80 and follower |40 and the uid pressure will cause follower |40 and', therefore, slide |05 to follow the contourof the cam. In order to avoid tool marks on the work upon the return of the` tool, fluid pressure is applied tothe inner side ofthe piston ||2 from pipe' |23 throughport ||8 before carriage 2 2 starts on its'return movement, thus causing` the slide |06 t be pulled away from# the work and cam. follower 40'to be vpulled away from the cam |88.. l

Hydraulic slideoperation and control Hydrauliccontrol of the slides is illustrated in Figs. 10, 11 and 13: Fig. 13vbeing a diagrammatic view o f the piping, cylinders, and valves, most of which are contained in one housing |4|, there rbeing one housing` 4| and associated parts for each carriage unit as shown in Figs. 10 and 11. Since the control andoperation of each carriage unit is the same, only one will be described.

Pipe |42 leads from an accumulator, or source of .fluid supply, frorri which .the'iluidmay be drawn in varying volume but under constant head, and is connected by pipes 2a-.with the stop valve casing y|48 (Figs. 10 and'13) one in Aeach housing I4|. A slidable stop valve |44 is in each 'valve casing |43 and each valve |44 is controlled by a lever |45 (Figs. 1, 2, 10, 11 and 13), in such a way, that when the valve I 441s in the position shown, fluid fromv Ythe source |42 isafre'e.

Yto Aflow through the valve casing |48 and; when moved to its other extreme position, the iiuidv source is completely shutoilr from the hydraulic system; From delivery port |48a -valve body |48 leads pipe |46 which lsupplies fluid pressure through varigus instrumentalities to the carriage cylinder |50 and cross-slide cylinder ||8 to' advance the carriage 22 .and/or slide |08 quicklyto the work-piece inv idle movements and slowly for work-performing or cutting oprations. From the delivery A|48a of valvebodyl |48 leads a pipe |41 which supplies iluid pressure to reverse of the cylinders |50 and ||8'. 4

-Frem pipe |41 leads' pipe m te the inner erv reverse side of cross-slide cylinder |I8, and from it also leads pipev |48 connected to the lower end or reverseside of carriage operating cylinder |58. T hus, when valve- |44 is open, there is always full pressure on the return side of Iboth the cross slide and the carriage operating pistons ||2 and |81 -to hold them in retracted position. A branch pipe |5| leads from pipe |46 to metering valve |52 having a needle valve |53 (the amount of opening of which is regulated by a threaded bushing or sleeve 53a) which is connected by pipe |54 `to pipe |55 to the outer or forward side of cross-slide cylinder ||3 by pipe ||1. Needle valve |53, when v connected to and controlled by the rotatable shaft of twenty-five pounds', while one port of valve |35^through lever |66 and link |6| (Figs. l, '1, 8, `10, 11 and 13) and which valve controls the fast 'fand slow feed and the reverse, in a manner hereinafter described. Leading from a mid-port |56 'in the` valve body |58 is pipel |62, connected with valve body |63, having valve |64 thereinoperated in a manner hereinafter described and which controls the operation vof the carriage 22. Pipe |54 from the metering valve |52 has branch 55a connected tothe pipe |62 which connects valves |59 and |63. -Also a branch pipe |61 connects regulator |66 with the pressure line between the stop valve |43 and the cross-slide cylinder |34, preferably being connected to pipe |55. Issuing from valve body |63 is pipe |69 which con' nects with the feedv side of thecarriage cylinder |56, and a3 branclr- |1|` from pipe |69 con- `nects with regulator |12, similarly as does pipe |61 with regulator |66,/` g

These regulators (or resistance valves, as they may be called) |66 and |12 are responsive to iluid pressure in the system to selectively direct said 'uid pressure4 to actuate the piston valves |59 and |64 which control the movement 'and speed 'of carriages 22 and cross-slides |66. These reguietersfflss en |12 are identical ineentruetion and have pilo valves |69 and |96, respectively,

which control non-metered Vfluid pressure from pipe |41 through branches |14 and' |16,- respectively, and are each connected with a drain pipe |16 through branch pipes |11. Pilot valve |69 of regulator |66 is also connected with one end of valve |63 through pipe |16, while pilot valve |66 of regulator |12 is similarly connected with theother end of control valve |66 through pipe |19 and is also connected with one end of control ,valvesl56 through pipes |19 andbranchpipe |66, 5

the other end of control valve |66 being connected ,to' hand lever |6| through link |6|. A One port of valve |66 is connected to drain' pipe l|16 by pipes`|6| and |62 having foot or check valve |66 interposed therein, which isset to maintain in the machine shown, a back pressure l, |63 is connected with drain pipe |16 by pipes |64 (the operation er the rig-ht hand slide only being and |65 having foot-or-check valvev |66 interposed therein which is set to maintain a back pressure offty pounds, in the machine shown. 'l 'I"he cycle of hydraulicoperations is as follows described) In following through the cycle of operations of this system, it isto be remembered .that the arrangement is suclLthat uid is taken from an accumulator of constant pressure (for example: 41100 pounds per square inch) and vthat all pipes which connect with the accumulator will mainly that the tool slides are positively stopped, however, pressure will build up to the maximum unless relieved. Q

At the beginning of a cycle, the carriage 22 is at its -extreme upward position and the cross-slide |66 in its extreme outward position, away from the work, with pistons ||2 and.|61 in the positions shown in Fig. 13. Piston |59 of valve |58 is in its extreme leftehand position, as shown in dotted lines, land'piston |64 of valve |63 is also in its extreme left hand position. With the valves l|56 and |64 in these positions, the fluid flows under pressure through stop valve |43, pipe |41 and pipe |23 to the reverse side of piston ||2, ,and through pipes |41 and |49 tothe reverse side of piston |61.

As Valve piston |59 is in the extreme leftposition covering port |46 further progress of the 2|5, thence through pipe |6I, foot valve |63 and pipe |82 to drain |16. In a similar way, the fluid from'the outer side of piston |2, escapes through pipes ||1, |55, |55a, |62 and ports |56 and 2|5 to pipe |6|,l foot valve |63, pipe |62 to drain |16.

The iluid from the advance or'upper side |16 of piston |61 flowsI through pipe |69 to ports 2|6 and 2|6 of valve |66 to pipe |64, foot valve |66 and fluid'under pressure in this direction is impospipe |65, to drain pipe |16. At the same time high pressure iluid from'pipe |41 is also passing from pipe |14 to port 265 of the regulator |66,

but as the pilot-valve |69 ,of said regulator is in the position showncoveri'ng port 205, no further movement of the fluid in this direction is possible. In 'the same way, a portion of the high pressure fluid flows from pipe |41 through pipe |15 to port 2|4 of`regulator|12 where it is similarly blocked by pilot valve |96 which is in the position shown covering port 2| 4. Therefore,

and |61 and the advance sides of these pistons V are open to the drain'; thus both slides are held high pressure is on" the reverse side of pistons H2 Y -onboth sides of the vcross-slide operating piston 2, but due' to the diameter of the piston rod the total pressure (or differential pressure) is greater on the forward side of the piston and the piston and rodmove rapidly in thedirection shown by the arrow, thus feeding the cross-slide in rapidly. As thev cross-slide approaches the work, the adjustable dog |62, Figs. 1, 8 and 9, is set so as to act on linger |66 of'lever |64 fast on (opposite to that movement previously impartedv shaft 13's, thus rocking shaft" las to an extent needle valve |53is opened by adjusting bushing |53a, thus the piston ||2 continues to advance slowly for cutting operations. During this operation it is to be understood, as explained above,

that the valve member |59 closes port |48, thus preventirg constant pressure in large volume from being transmitted to the cylinder ||3. Dur-` ing this slow advancing movement for cutting operations of the piston H2, the reverse sideof the piston ||2 is acting against constant pressure being introduced at thereverse side of the cylin-v 4der I|3 through` pipes |41 and |23, but due `to the area of the piston rod i the effective pressure on the reverse side of the piston is less than on. the forward feeding sideand the piston 'advances.

When the cross slide |06 reaches the end of its stroke, it abuts against stop screw |21 (Figs. 8, 9, 10) in carriage 2 2, which prevents further forward movement. Pressure then immediately begins to build up inV the high pressure line 1, |55, branch pipe |61 of regulating valve |68 and tends to move ,valveplunger |93 against the resistance of spring i 94 which is adjusted by threaded bushing |95, to resist pressure of 1000 pounds per square'inch. When pressure is high l enough to overcome the resistance of this spring,

plunger |93 is moved, and by shoulder |96 thereon, leverv |91 pivoted on pin |98,v starts to move valve plunger |89 in the direction shown by the arrow., This movement is relatively slow.

until jaws |99 on lever/|91 get over the center, when it is snapped quickly the rest of the way by means of spring A200 on rod'20l pivoted on pin 202. This quick movement is allowed by thel extra space between lshoulders |96. and 203 on plunger |93. As piston |89 is slowly moved in is thrown to its extreme position.

occurs, port 205 is uncovered and put into comthe direction of the arrow, port'A 204 which is rst covered by piston |89, is not uncovered until the ,quick snap takes place and valve piston |89 When this munication with port 206 and the high pressure4 iluid flows from pipes |41, |14 to pipe |18.to the left hand end oi' valve |63 where it causes valve Apiston |64 to move quickly to its extreme right position, the fluid inv the chamberl92 on the right hand end of valve. piston |64 escaping v through pipe |19, port 201 of regulating valve |12 thence, to port 208wl1'ere itv drains into the f body of valve |12, and from thence out through fpipe |11 to the drain pipe 16. Throwing valve plunger |64 tothe right puts portv 209'in communication with port 2|0 and allows/ the fluid'y to flow from metering valve |52 through pipes |54, |55a, |62, valve1 |63l through pipe |69 to the advance side |10-of piston |81 causing it, by means of the-beforementioned differential pressure,.to feed thecarriage 22 slowly downward, the rate of,feed dependingas before, on the I amount of openin'gof needle valve |53. As soon ,as piston |81 starts t`o move downward, the pressure in line` |61 accumulated bythe stopping of pistonv I2, drops below 'that necessary to move 'in the position shownin-Fig. 13, quicksnap of lever |91 takes place on this re- .,seating, as on the original movement of the' ras' L I plunger |93 and spring |94l causes plunger |93 to move back to its original position as shown.,

in Fig. 13, this action also reseatingI valve |89 The same valve. y

'Ihe play,lbetween the end of lever |91 and collars |96 and 208- on plunger |93 is necessary`r because ifi there was no play, as pressure built up in line |61 sufficient to overcome the pressure of spring |94, plunger |93 would move, and by lever |91 move valve plunger |89 in the di` rection of the arrow. As soon as this valve.

plunger had moved sufllciently to connect ports 205 and 206 fluid would immediately start to ilow through pipe |18 to the end of valve |64, moving it to the right. Immediately port 209 was allowed' to communicate with port 2|0, pressure in line |61 would drop and plunger |93 wouldl'immediately be started back by spring |94,

thus moving valveipiunger |69 to close port 205.

This operation might take place before the fluid had a chance to move plunger |69 to its extreme right position, and such action would be detrimental. The extra play between the end of lever' `|91 and the collars on plunger |99 and the quick snap causedby spring 209 to lever' |91- after ity has crossed the center, provide a suillcient dwell or delay to plunger |89 to allow the operations to be completely carriedout. l Since the valve |64 is in its extreme right hand position, communicating ports 299 and 2in and valve |59 is in its mid position closing ports |49v and 2|5, metered fluid pressure ilows from pipe |54 through pipe |69` to continue the movement Vof carriage 22 downwardly until the carriage kvalve |68, (the same as previously described in connection with cylinder ||9 for the purpose of moving plungerl|93 against the tension of spring |94 set for 1000 pounds of pressure per squarelinch), but as pipe |69 is also connected with plunger zii of reginato'r valve' arrbypipe m this build-up pressure will rst actuate plunger 2|| against the tension of spring 2|2 set at a lower pressure than spring |94, say for instance 900 pounds to the square inch. When the pressure reaches 900 pounds per square inchplnger 2 starts to move, and throws pilot valve |90 by means of lever 2|3, (in the same way as that hereinbefore described-in connection withvalve les) thus connecting port 2| 4 .with port'znr and allowing `the high pressure 'iluid from the live pressure line |41, to pass through pipe |15, ports. 2|4 and 201 and pipe |19 to the right, hand side s of `valve piston |64 throwing it to its extreme left position, shown in the drawings, the fluid from thel left hand ide of valve piston |64 es- .caping through pipe |18, port 206, port 204 to the interior ofvalve casing |68, fromwhence it;- escapes` to the drain through pipes |11 and |16.

At the same timethis high pressure also passes .from regulating valve |12 through pipes |19Aand |80 to the right hand .end of vaivepiston |59,` throwing -it to its lextreme leftposition shown in dotted lines. 'I'he advance side |66 of cross slide cylinder H3 is now connectedwith the drain pipe |16 through pipes |91, |55, |66a, |62, ports |56.

and the advance side |16 of piston |61is now connected with the drain |16 through pipe |68,

' port 2i0, port, 2|6, pipe |84, foot valve |86 and pipe |85; and asthere is always present high pressure on the reverse side of pistons Il! and |81 from the live pressure line |41 they tend to A reaches its extreme retracted or upper position.

be pushed back. Foot valve |86 a) higher pressure than foot valve |68. For example, |86 may be set atvflfty pounds per square inch and |83 at twenty-live pounds per square inch. Therefore, due to the peculiarities of now of liquid from. an accumulator, the extra. back pressure on valve |86 will keep' piston |81 from' starting .its reverse movement until piston Il! has reached its extreme outer or retracted position. Then piston |81'will start baci:l until it .'Ihe pistons and valves and slides are no w in their original position, ready to Xstart. another' cycle upon operation of plunger' valve |68 by hand lever ISI.

If, at any time, it is desired stop or start the.

machine' during a cycle, that can be done through rates of movements, a pressure receiving element controlling -uid pressure delivered to said .cylinstop valve |44 by means of-hand lever |46 (Figs. l, 10, 1-1 and 13). In the cycle'of operation, yas above described, the valvel piston |66 is shifted from the fast ahead position shown in full lines e of Fig. 13, to the slow feed ahead position (a middie position of thevalve to close ports |48 and 2li) during the forward movement of the cross slide |06,A but it is evident that the throwing ot this valve into the slow f fer'red until any pointi A. the forward cycle of veither the cross slide or the carriage. or it may not-be shifted to the feed position at all. in which mot'on. It is also lcontemplated and within the purview of this inventioxrthat the)carrlage 22 (or Vits like counter-part) may be actuated `before the` slide |06 in the beginningA ofthe machine oper'- ating cycle. l That which is claimed is:

1. In a'fluid `pressure mechanism for machine'- tools having a movable member whose rate of movement in one direction is to be changed, a source ofY constant fluid pressure to effect all suchv connected with said movable member, means for establishing fluid pressure connection between said pressure source and the fluid pressure receiv- .ing element, a valve means in said connection means for changing the rate oi.' movement of the movable member and including a valve element for varying the amount of fluid delivered to the pressure receiving .element from said supply source, and a second valve element for controlling the delivery of larger volume to said pressure receiying element from said source whereby the rate of movement of saidniember may be changed.

2. In a uld pressure mechanism'as in claim 1 said valve means including means for relieving the pressures on said pressure receiving element, and rmeans .for moving saidvmember in reverse direction when said pressures are relievedif, 3. In a mechanism asin claim l in which the pressure receiving element isthe piston of a hydraulic cylinder and there is a second movable isset to resist position may be decase the complete 4cycle will take place on the fast 2,118,022 and :is to pipe isi, fooi; valve m and pipe In,

member likewise operatively connected with the piston of. another hydraulic cylinder, and in which thefluid connectionimeans extends betwensaid valve means and both of said cylinders and means for automatically controlling the flow of said -fluid through said connections for obtaining a sequential operation, of said members.

, 4. In a uid pressure mechanism for machinevtools as set. forth in claim l wherein said valve means includes means for relieving the said pres: sures on said pressure-receiving element and wherein there is fluid passage means supplying a Aconstant pressure to the pressure-receiving ele# ment to move and retain said member in a re- ,'tracted position and to yieldingly resist the movement of the 'member in` the other giirection.

5. A iluid pressure mechanism lfor operating a vsingle moving member, or a plurality of moving niiemberscomprising a constant pressure source of iluid supply; member moving means whereby pressure maybe exerted on such lmeans to advance or retract a member, aforesaid; a constantly open connection between the constant pressure source of iluid supply andthe retraction side of Athe member-moving means; means forconnecting the advance side of the member-moving means with either a drain line, a source of iiuid under ,constant pressure in ilarg'e volume, or a source of vfluid under constant pressure in small Avolume: means for metering the constant pressure fluid supply, means for, producing back pressure in the drain line, and a quick-acting means operated by variation in pressure to automatically change the huid ilow. Y

6.` Inl a fluid pressure mechanism lformahinetools'ha'ving a fluid metering needle valve, and' means to rotate said valve while the mechanism is in operation.

1, In a uid pressure mechanism for machine tools that have to and fro. moving members, a

quick laction valve that' controls the fluid pressure acting on such a member, automatic means to operate said valve comprising a fluid pressure moved; ,plunger, means yieldingly opposingmove- `lment if said plunger by uid pressure,'and an.

operatlvepconnectio'n between the plunger and said valve acting by movement of the plunger underlfiluid pressure lin excessof the yieldable movement opposing means. f v :8. A Vuidpressure mechanism for a machinetool thatv hasa plurality of to and fro moving slides,a hydraulic cylinder and piston operatively connected with each slide, a source of supply of uid pressure, piping leading from s uch source to each of said cylinders, a valve in such piping for ders, a second valve means in said piping adapted to causeiast andslow movements to the slides and tareverse the direction thereof, a resistance valve ,in said piping for each hydraulic cylinder and subject to pressure supplied to the respective I a rslide on said carriage having a follower block,

a. housing on'said carriage, a former cam; a bar carrying the cam and slidable in said housing, hy-

draulic means for Vplacing the slide'follower block in contact with the foromer cam holding it there and retracting it; andvmeans for imparting rela# tive movement to slide and former cam.

10. A machine-tool comprising two spaced apart units, a lower unit constituting an upright base, means mounted 'on suchbase for imparting .release the same and rotation tothe work' and including a vertical spindle; the other unit being an upper unit supporting tool-feed mechanism and including a horizontal bottom `feed-works supporting plate, a plurality of vertical bars rigidly supported at their lower ends in the 'lowenunit and extending upward to the underside oi said plate and vrigidly connected tosaid plate,- tool slides mounted to reciprocate on said bars, and r operative connections between the feed-works above said plate and y ,A said slidesreaching downward from said plate.

ll. A macliine=tcol comprising two spaced apart units, a lower unit constituting anupright base,-' means mounted on the base for imparting rotation to the work and including a vertical v l spindle; the other unit being an upper unit supporting tool feed mechanism and including a horivzontal bottom feed work supporting plate, aplurality of `vertical bars rigidly supported at their lower ends in the lower unitand extending upward to the underside of said plate and rigidly connected to said plate, tool slides mounted to reciprocate on said bars, 'and operative connections between* the feed works above said plate and said slides preaching downward from said plate,4 said. operative connections comprising membersV of hydraulic mechanism situated-above said plate. y

12. In a machine-tool, a plurality of members' adapted to cooperate with respect Vto a work piece in the machine, means members tol and from thework piece, means for locking said member vin one of its vmovements and comprising a clamp ymeans, said member moving means having a loose connection with said member whereby said 'member moving means may continue movement after the-movement of said member has been arrested in one direction and will iirst move in the opposite direction before correspondingly. m ving said member, said member movingmeans avingan operable connection with said clamping means same Ior clampirg said member when it has been arrested in its movement in -one direction and for .releasing said'clamping meanswhn initially moved in the opposite direction. i

i3. In a machine-tool' asset iorth'in claim l1 further characterized by said member moving.

- means including a fluid pressureactuating def back pressure in said devic Avice for operatingsaid moving means in opposite directions, and means for gradually releasing said' member toward the workpiece in the machine.

in the machine, means for moving one of vsaidl members to and from thework-piece, said memhaving `a` work engaging part, a support .for said memberv with respectI to which it moves, a clampingelement positionedtol engage vand bind l against said support, means connecting said 'to bind said element against said support and to clamping element and said member and operable .members vertically for moving one of said to operate the e in the movement of 14. 1n amacmnecool' as setrorni incmlm i1 Vance sideof said piston,

fthe same.

' stant A pressure supply .ton into and maintaining the same in a for controlling and varying including a rotatable rod, said member moving means' having a yielding slidable connection with when the member is arrested in its movement to lengage the work-piece -said moving means will moving means is initially operated to withdraw said member so that .fil

work-piece and will be again actuated when the said member from the work-piece, but before said member is actually moved,

1'6. In a machine-tool, a plurality of members adapted to cooperate with respect to a work-piece,

in the machine, means for moving one of said said member having a work engaging part, a support forl said member with respect to which'it moves, a clamping element positioned to vengage and bind against said support, means connecting said clamping element and said member and opagainst said support erable to bind said element and to release the same and including a rotatable rod, said member moving means having-a loose sldable 'connection with said member so that when the member is arrested in its downward movement by engagement with the work-pieceA said moving means will have a further downward movement, and an operative connection between said moving means and said rotatable rod, wherebythe clamping element will be actuated after to and from the work-piece,

said member has been brought to rest in its downward movement and will be again actuated when the moving means' initially operated to raise said member. `but vbefore said member is actually moved., v-

17.1n a fluidfpressure mechanism for a machine-tool which has a to and fro moving -member; a hydraulic-cylinder anda pistontherein operatively connected with said member for mov-y ing the latter, in two directions, a source oi constant pressure `supply having a constantly open connection with said 'cylinder for moving said piston into and maintaining the same in a posi'- tion to retract said member, another connection between said source Vof supplyand said cylinder to operate said piston to feed the member forwardly, means in said second connection for controlling the ilow of fluid pressure to said cylinder at the memberadvancing side of said piston, means in said second connection and responsive to back Ipressure for actuating said first menthe pressure on the adwhereby the pressure on tioned means to relieve and the retraction side (of said piston will operate essure mechanism for a machine-tool which has a to and fro moving member, a hydraulic cylinder and a piston to operate said piston to ,feed 'the member forwardly, said second connection including means the fluid pressure delivered to the advance side l of said piston whereby the rate of advanced movement of said piston may be varied, andmeans in said second connection and responsive to back pressure for actuating said' iirst mentioned means to relieve the pressure onthe advance side of said piston, whereby the pressure onthe retraction side of said piston will operate the same.

nection with the cylinders at the retraction side of each of` said pistons for moving said pistons into and maintaining the same in positions to retract said members, another connection between said source of supply and said cylinders at the advance side of their respective pistons, a valve means in said second connection operable to deliver suflicient pressure to one of said pistons to advance the latter fromv its retracted position, means responsive to back pressure in the advance pressure line of said last mentioned piston to operate said valve means for 'admitting pressure to the advance side of the other of said pistons, and another means responsive to pressure inxthe advancevpressure line of said'other piston for operating said valve means to cut off the. advancing' pressure to each of said cylinders whereby the constant pressure .at the retraction sides of said pistons will become veiective for retracting the same. I Y

20. In a iiuid pressure mechanism for a machine-tool as set forth in claim 19, further characterized by other pressure responsive means in said connections responsive to the said back pressure in said advance side of said cylinders for allowing one of said pistons to be retracted before the other of said pistons. Y

21. In a fluid pressure mechanism for operating a moving member or a plurality of moving vmembers of a machine tool,` which mechanism comprises a source of constant pressure fluid supply, means for moving said member by said iiuid pressure to advance said member or retract thev same, a constantly open connection between said pressure supply source andthe retraction side of said member moving means, means'for connect-4 ingthev advance side ot said member moving means with said pressure supply source`and to a drain, and valve means in said last mentioned4 connecting means for controlling the pressure therein to said member moving means, and means in said advance side connection and by-passing said valve means tor metering the constant pressure supplyn from said source to the advance side of said member moving means. l

22. In a fluid pressure mechanism as set forth in claim 21 further characterized by means for producing a back pressure in said advance side connecting means, and a pressure device responsive tovariations in the pressure in said advance side connecting means fo'r automatically relieving the pressure therein when predetermined pressure has been reached.

, v23. In a uid pressure mechanism asset forth in claim 21 further characterized by a second to and fro movable member andv means for operating said member, an open connection between'the said source of duid pressure and said last mentioned`member moving means for retracting said second member; anotherconnection between said last mentioned member moving means, the outlet sideof said r'st" mentioned valve means and the outlet side of said metered pressure connection foradvancing said second member, anda second valve means in the Ladvance side connection of said last mentioned member movingmeans for opening and closing the same, means in .the ad- Vance side connections and respgnsive to pressure therein from the member moving means, a

connection between said pressure responsive means and said second valve means to effect the advancing operation bf said second member, and a connection between` said pressure responsive means and bothof seid valve means for rendering the pressure in MYRON s.- CURTIS,

said member advancing connections ineffective. y 

